A proposed configuration of a surgical navigation system uses a retina projection-type head-mounted display (RPHMD) to project three-dimensional simulation image information of an implant on the retina of a surgeon to be overlapped on an operation site of a patient (as described in, for example, PTL 1). This system measures three-dimensional position posture of a first marker that is fixed in the mouth of the patient and three-dimensional position posture of a second marker that is fixed in the RPHMD, converts the three-dimensional simulation image information of the implant from a three-dimensional coordinates system into a surgeon field-of-view coordinates system by using the three-dimensional position postures of the first marker and of the second marker, three-dimensional position posture between the implant and the first marker, and position of the second marker, and uses the RPHMD to project the converted three-dimensional simulation image information on the retina of the surgeon to be overlapped on the operation site of the patient.
Another proposed configuration of the surgical navigation system generates a three-dimensional image for surgical navigation by using a photographed three-dimensional image that is taken by a binocular camera that tracks a patient and a surgical instrument, and overlaps the generated three-dimensional image on an operation site of the patient (as described in, for example, NPL 1). This system generates a three-dimensional image for surgical navigation by tracking of the patient and three-dimensional contour matching without requiring markers, and displays the generated three-dimensional image on a three-dimensional display to be overlapped with the operation site of the patient via a half mirror.